Wireless patient monitoring system and method

ABSTRACT

A patient monitoring system includes at least two wireless sensing devices, each configured to measure a different physiological parameter from a patient and wirelessly transmit a parameter dataset. The system further includes a receiver that receives each parameter dataset, a processor, and a monitoring regulation module executable on the processor to assign one of the at least two wireless sensing devices as a dominant wireless sensing device and at least one of the remaining wireless sensing devices as a subordinate wireless sensing device. The physiological parameter measured by the dominant wireless sensing device is a key parameter and the parameter dataset transmitted by the dominant wireless sensing device is a key parameter dataset. The key parameter dataset from the dominant wireless sensing device is processed to determine a stability indicator. The subordinate wireless sensing device is then operated based on the stability indicator for the key parameter.

BACKGROUND

The present disclosure relates generally to medical devices and, morespecifically, to medical monitoring devices for monitoring a patient'sphysiology and health status.

In the field of medicine, physicians often desire to monitor multiplephysiological characteristics of their patients. Oftentimes, patientmonitoring involves the use of several separate monitoring devicessimultaneously, such as a pulse oximeter, a blood pressure monitor, aheart monitor, a temperature monitor, etc. Several separate patientmonitoring devices are often connected to a patient, tethering thepatient to multiple bulky bedside devices via physical wiring or cables.Multi-parameter monitors are also available where different sensor setsmay be connected to a single monitor. However, such multi-parametersystems may be even more restrictive than separate monitoring devicesbecause they require all of the sensors attached to a patient to bephysically attached to a single monitor, resulting in multiple wiresrunning across the patient's body. Thus, currently available patientmonitoring devices often inhibit patient movement, requiring a patientto stay in one location or to transport a large monitor with them whenthey move from one place to another.

Further, currently available monitoring devices are often powerintensive and either require being plugged in to a wall outlet orrequire large battery units that have to be replaced and recharged everyfew hours. Thus, monitoring multiple patient parameters is powerintensive and battery replacement is costly in labor and parts. Thus,frequent monitoring is often avoided in order to limit cost and patientdiscomfort, and instead patient parameters are infrequently spotchecked, such as by periodic nurse visits one or a few times a day.While there are some patients that require continuous, real-timemonitoring, such as those patients experiencing a critical healthcondition, the vast majority of patients need only periodic monitoringto check that their condition has not changed. However, patients thatare not being regularly monitored may encounter risky health situationsthat go undetected for a period of time, such as where rapid changesoccur in physiological parameters that are not checked by a clinicianuntil hours later or until a critical situation occurs.

SUMMARY

The present disclosure generally relates to a patient monitoring systemand method.

A patient monitoring system includes at least two wireless sensingdevices, each wireless sensing device configured to measure a differentphysiological parameter from a patient and wirelessly transmit aparameter dataset. The system further includes a receiver that receiveseach parameter dataset from each of the at least two wireless sensingdevices, a processor, and a monitoring regulation module executable onthe processor. The monitoring regulation module is executable to assignone of the at least two wireless sensing devices as a dominant wirelesssensing device and at least one of the remaining wireless sensingdevices as a subordinate wireless sensing device. The physiologicalparameter measured by the dominant wireless sensing device is a keyparameter and the parameter dataset transmitted by the dominant wirelesssensing device is a key parameter dataset. The key parameter datasetfrom the dominant wireless sensing device is processed to determine astability indicator for the key parameter. The subordinate wirelesssensing device is then operated based on the stability indicator for thekey parameter.

One embodiment of a method of monitoring a patient includes providingtwo or more wireless sensing devices, each wireless sensing deviceconfigured to measure a different physiological parameter from apatient. Each wireless sensing device is communicatively connected to acomputing system having a processor. The method further includesassigning at the processor one of the at least two wireless sensingdevices as a dominant wireless sensing device, and assigning at leastone of the remaining wireless sensing devices as a subordinate wirelesssensing device. The dominant wireless sensing device is then operated tomeasure a key parameter from the patient and wirelessly transmit a keyparameter dataset. The method further includes processing the keyparameter dataset to determine a stability indicator for the keyparameter, and selectively operating the subordinate wireless sensingdevice based on the stability indicator for the key parameter.

Various other features, objects and advantages of the invention will bemade apparent from the following description taken together with thedrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode presently contemplated of carryingout the disclosure. In the drawings:

FIG. 1 provides a schematic diagram of one embodiment of a wirelesspatient monitoring system.

FIG. 2 provides a schematic diagram of another embodiment of a wirelesspatient monitoring system.

FIG. 3 provides a schematic diagram of one embodiment of a computingsystem portion of a wireless patient monitoring system of the presentdisclosure.

FIG. 4 depicts one embodiment of a method of monitoring a patient.

FIGS. 5-8 depict various embodiments of a method of monitoring apatient.

DETAILED DESCRIPTION

The present inventors have recognized that wireless monitoring systemsare desirable for patient comfort, for example to provide more comfortand mobility to the patient being monitored. The patient's movement isnot inhibited by wires between sensor devices and/or computing devicesthat collect and process the physiological data from the patient. Thus,small sensing devices and sensors that can be easily attached to thepatient's body are desirable, such as sensing devices that are wearableportable computing devices. In order to do so, the size of the wirelesssensing devices must be small. The present inventors have recognizedthat an important aspect of decreasing the size and weight of wirelesssensing devices is decreasing battery size, and that a weakness in thedevelopment of wireless sensing devices has been power consumption andrequirement for long battery times.

In view of their recognition of problems and challenges in thedevelopment of wireless sensing devices, the present inventors developedthe disclosed system and method to minimize power consumption of thewireless sensing devices. As provided herein, battery demand for eachwireless sensing device, and thus power requirements for the system as awhole, are decreased by selectively and intelligently operating one ormore of the wireless sensing devices on an infrequent basis when thepatient's condition is stable and continuous patient monitoring isunnecessary. In the patient monitoring method and system disclosedherein, a dominant wireless sensing device is assigned, such as based onthe patient's condition and/or medical or treatment history, and otherwireless sensing devices in the system are controlled based on thecondition of the patient as determined by the data gathered from thedominant wireless sensing device. Accordingly, the wireless sensingdevices are intelligently controlled to enable maximum continuouspatient monitoring capabilities when necessary, but can be operated in areduced monitoring mode when the patient seems stable in order to reducethe power requirements of the wireless sensing devices and increase thebattery life of those devices. This will decrease the cost associatedwith the wireless monitoring system as a whole, including reducing thedemand on clinicians to change and charge batteries for the subordinatedevices, decreasing the wear on the subordinate devices, while providingsufficient patient monitoring such that deterioration of the patientcondition will be timely detected.

Another benefit of the system and method disclosed herein is that thesystem automatically determines when the patient condition hasdeteriorated based on the data gathered from the dominant wirelesssensing device and automatically initiates increased or continuousmonitoring by all wireless sensing devices. Thus, when a clinicianresponds to an alarm condition, recent monitoring data is alreadyavailable and is being updated for all relevant physiological parametersmonitored by the system. This is an improvement over prior art systems,where clinicians responding to an alarm condition are required toinitiate monitoring by various monitoring or sensing devices and waitfor those devices to produce measurements in order to fully assess thepatient's condition.

In various embodiments, wireless sensing devices measuring differentphysiological parameters may be networked to a central hub or primarysensing device that controls the wireless sensing devices in thenetwork. The hub may communicate with a central, host network, such asof the medical facility. In another embodiment, the wireless sensingdevices may communicate with the host network that calculates thepatient stability index and assigns the measurement intervals. There,the wireless sensing devices may communicate with the host networkdirectly, or indirectly through the hub. For example the hub may serveas an amplifier and/or router for communication between the wirelesssensing devices and the host network.

FIG. 1 depicts one embodiment of a patient monitoring system 1containing five wireless sensing devices 3 a-3 e in wirelesscommunication with a hub device 15 to form monitoring network 51. Forexample, the hub device 15 may be attached to the patient's body, placedon or near the patient's bed, or positioned within range of the patient,such as in the same room as the patient. The hub device 15 may be aseparate, stand alone device, or it may be incorporated and/or housedwith another device within the system 1, such as housed with one of thewireless sensing devices 3 a-3 e. The hub device 15 is also in wirelesscommunication with a host network 30 that contains medical recordsdatabase 33.

Each wireless sensing device 3 a-3 e contains one or more sensors 9 a-9e for measuring a physiological parameter from a patient, and alsoincludes a base unit 10 a-10 e that receives the physiological parametermeasurements from the sensors 9 a-9 e and transmits a parameter datasetbased on those measurements to the hub device 15 via communication link11 a-11 e. The sensors 9 a-9 e may be connected to the respective baseunit 10 a-10 e by wired or wireless means. The sensors 9 a-9 e may beany sensors, leads, or other devices available in the art for sensing ordetecting physiological information from a patient, which may includebut are not limited to electrodes, lead wires, or availablephysiological measurement devices such as pressure sensors, flowsensors, temperature sensors, blood pressure cuffs, pulse oximetrysensors, or the like.

The depicted embodiments include five wireless sensing devices 3 a-3 ein the monitoring network 51. A first wireless sensing device 3 a is anECG sensing device having sensors 9 a that are ECG electrodes. A secondwireless sensing device 3 b is a non-invasive blood pressure (NIBP)sensing device with a sensor 9 b that is a blood pressure cuff includingpressure sensors. A third wireless sensing device 3 c is a peripheraloxygen saturation (SpO2) monitor having sensor 9 c that is a pulseoximetry sensor, such as a standard pulse oximetry sensor configured forplacement on a patient's fingertip. A fourth wireless sensing device 3 dis a temperature monitor having sensor 9 d that is a temperature sensor.The depicted embodiment of the system 1 further includes a fifthwireless sensing device 3 e that is an EEG monitor having sensors 9 ethat are EEG electrodes. It should be understood that the patientmonitoring system 1 of the present disclosure is not limited to theexamples of sensor devices provided, but may be configured and employedto sense and monitor any clinical parameter. The examples providedherein are for the purposes of demonstrating the invention and shouldnot be considered limiting.

The base units 10 a-10 e of each of the exemplary wireless sensingdevices 3 a-3 e may include analog-to-digital (A/D) converters 13 a-13e, which may be any devices or logic sets capable of digitizing analogphysiological signals recorded by the associated sensors 9 a-9 e. Forexample, the A/D converters 13 a-13 e may be Analog Front End (AFE)devices. The base units 10 a-10 e may further include processors 12 a-12e that receive the digital physiological data from the A/D converters 13a-13 e and create a parameter dataset for transmission to the hub device15 and for the host network 30. Each base unit 10 a-10 e may beconfigured differently depending on the type of wireless sensing device,and may be configured to perform various signal processing functions andor sensor control functions. To provide just a few examples, theprocessor 12 a in the ECG sensing device 3 a may be configured to filterthe digital signal from the ECG sensors 9 a to remove artifact and/or toperform various calculations and determinations based on the recordedcardiac data, such as heart rate, QRS interval, ST-T interval, or thelike. The processor 12 b in the NIBP sensing device 3 b may beconfigured, for example, to process the physiological data recorded bythe sensors 9 b in a blood pressure cuff to calculate systolic,diastolic, and mean blood pressure values for the patient. The processor12 c of the SpO2 sensing device 3 c may be configured to determine ablood oxygenation value for the patient based on the digitized signalreceived from the pulse oximetry sensor 9 c. The processor 12 d of thetemperature sensing device 3 d may be configured to, for example,determine a temperature for the patient, such as a mean temperaturebased on the digitized temperature data received from the thermal sensor9 d. And the process or 12 e of the EEG sensing device 3 e may beconfigured, for example, to determine a depth of anesthesia measurementvalue, such as an entropy value or a sedation responsiveness indexvalue.

Accordingly, the processor 12 a-12 e may develop a datasets that, inaddition to the recorded physiological data, also include valuesmeasured and/or calculated from the recorded physiological data. Therespective processors 12 a-12 e may then control a receiver/transmitter5 a-5 e in the relevant wireless sensing device 3 a-3 e to transmitparameter datasets to the hub device 15 via communication link 11 a-11e. The parameter dataset transmitted from the respective wirelesssensing devices 3 a-3 e may include the raw digitized physiologicaldata, filtered digitized physiological data, and/or processed dataindicating information about the respective physiological parametermeasured from the patient.

In other embodiments, the processors 12 a-12 e may not perform anysignal processing tasks and may simply be configured to performnecessary control functions for the respective wireless sensing device 3a-3 e. In such an embodiment, the parameter data set transmitted by therespective processor 12 a-12 e may simply be the digitized raw data ordigitized filter data from the various sensor devices 9 a-9 e.

Each wireless sensing device 3 a-3 e includes a battery 7 a-7 e thatstores energy and powers the various aspects of the wireless monitor.Each processor 12 a-12 e may further include power managementcapabilities, especially where the respective wireless sensing device 3a-3 e contains more demanding electromechanical aspects. Each processor12 a-12 e may monitor a battery status 43 a-43 e (FIG. 3), such as acharge level of the relevant battery 7 a-7 e. The processor 12 a-12 emay communicate the battery status to the hub device 15 by thecommunication link 11 a-11 e. Alternatively or additionally, theprocessor 12 a-12 e may control a local display on the wireless sensingdevice 3 a-3 e to display the battery status 43 a-43 e, and/or maycontrol the emission of an audio and/or visual alert regarding thebattery status 43 a-43 e.

The receiver/transmitter 5 a-5 e of each wireless sensing device 3 a-3 ein the monitoring network 51 communicates via the respectivecommunication link 11 a-11 e with the receiver/transmitter 17 of the hubdevice 15, which may include separate receiving and transmitting devicesor may include an integrated device providing both functions, such as atransceiver. The receiver/transmitters 5 a-5 e of the wireless sensingdevices 3 a-3 e and the receiver/transmitter 17 of the hub device 15 maybe any radio frequency devices known in the art for wirelesslytransmitting data between two points. In one embodiment, thereceiver/transmitters 5 a-5 e and 17 in the monitoring network 51 may bebody area network (BAN) devices, such as medical body area network(MBAN) devices. For example, the wireless sensing devices 3 a-3 e may bewearable or portable computing devices in communication with a hubdevice 15 positioned in proximity of the patient. Other examples ofradio protocols that could be used for the monitoring network 51include, but are not limited to, Bluetooth, Bluetooth Low Energy (BLE),ANT, and ZigBee.

The hub device 15 may further include computing system 35 havingprocessor 19 and memory 21. The hub device 15 may serve to control thewireless sensing devices 3 a-3 e, and thus may transmit operationcommands 45 a-45 e (FIG. 3) to the respective wireless sensing devices 3a-3 e via the communication link 11 a-11 e to control their monitoringoperations. The hub device 15 may contain a monitoring regulation module23 that is a set of software instructions stored in memory andexecutable on the processor to assess the physiological data collectedby the wireless sensing devices 3 a-3 e and determine a patientcondition therefrom, and to control the respective wireless sensingdevices 3 a-3 e according to the patient condition.

For example, the monitoring regulation module 23 may be configured toassign one or the wireless sensing devices 3 a-3 e as a dominantwireless sensing device that will be used to gauge the patient'scondition and to control the frequency of operation of one or more ofthe other wireless sensing devices in the monitoring network 51, whichbecomes the subordinate wireless sensing devices. The physiologicalparameter measured by the dominant wireless sensing device is a keyparameter that is used to assess the stability of the patient'scondition based on the data measured from the dominant wireless sensingdevice, the key parameter dataset. The key parameter and the dominantwireless sensing device may be selected based on a diagnosis or atreatment history for the patient. For example, a patient being treatedfor a particular condition may be assigned a key parameter that is mostrelevant to monitoring the patient's condition, such as thephysiological parameter most associated with or most impacted by thepatient's condition or diagnosis. Likewise, if the patient is undergoingor recovering from a particular treatment or procedure, then the keyparameter may be the physiological parameter that is most likely to beimpacted or to signal complications associated with recovery from theprocedure. For instance, electrical activity of the heart is likely tobe a key parameter for a patient that is diagnosed with and/or beingtreated for a heart condition or has recently undergone a cardiacprocedure. In that instance, the wireless ECG sensing device 3 a may beassigned as the dominant wireless sensing device, and one or more of theremaining wireless sensing devices may be subordinate wireless sensingdevices controlled based on the key parameter dataset measured by theECG sensing device 3 a, which is the dominant wireless sensing device.

The monitoring regulation module 23 may process the key parameterdataset 41 a (see FIG. 3) from the dominant wireless sensing device todetermine a stability indicator for the key parameter, and thesubordinate wireless sensing devices may be selectively operated basedon that stability indicator. For example, if the stability indicator forthe key parameter is within a range that can be considered “stable”,then the patient condition is assumed to be stable and the subordinatewireless monitoring devices may be operated in a way to conserve theirpower consumption.

As illustrated in the embodiment shown in FIG. 1, the ECG sensing device3 a is assigned as the dominant wireless sensing device, and theremaining wireless sensing device 3 b-3 e in the monitoring network 51are assigned as the subordinate wireless sensing devices. In otherembodiments, some subset of the remaining wireless sensing devices 3 b-3e may be assigned as subordinate wireless sensing devices and controlledbased on the dominant wireless sensing device 3 a. In that embodiment,those wireless sensing devices not assigned as subordinates could beindependently controlled. In the depicted embodiment, the dominant ECGsensing device 3 a may be operated to continuously monitor theelectrical output of the heart as the key parameter for assessing thepatient's condition. The output of the dominant ECG sensing device, keyparameter dataset 41 a, may then be continually processed to determine astability indicator for the ECG. The remaining wireless sensing devices3 b-3 e may then be selectively operated based on the stabilityindicator. For example, as explained in more detail herein, one or moreof the subordinate sensing devices may be turned off and only activatedif the key ECG parameter dataset is determined to be unstable.Alternatively or additionally, one or more of the subordinate wirelesssensing devices may be operated at a minimum measurement interval, whichmay be a minimum interval set for each wireless sensing deviceindividually.

For example, a minimum measurement interval may be stored for eachsubordinate wireless sensing device 3 b-3 e and the monitoringregulation module 23 may instruct operation of each subordinate wirelesssensing device 3 b-3 e at its minimum measurement interval if thestability index indicates that the key parameter dataset 41 a is stable.If the stability index indicates that the key parameter is unstable, themonitoring regulation module 23 may instruct one or more of thesubordinate wireless sensing devices 3 b-3 e to increase the monitoringfrequency above the minimum measurement interval as appropriate based onthe degree of instability indicated by the patient condition index. Forexample, the monitoring regulation module 23 may increase themeasurement interval proportionally to the level of the stability index,and may instruct any level of monitoring between the minimum measurementinterval for each subordinate wireless sensing device and continuousmonitoring for each subordinate sensing device depending on thestability index. The minimum measurement interval may be different foreach wireless sensing device 3 a-3 e, and may account for the patient'sdiagnosis, medical history, procedure history, previous monitoring data,etc. For example, the minimum measurement interval may be set to zerofor a wireless sensing device measuring a parameter that is unimportantto the general monitoring of a patient, but might provide importantinformation if the patient's condition begins to deteriorate. In thatinstance, that subordinate wireless monitoring device may be turned offcompletely or operated in a low power mode unless the stabilityindicator for the key parameter is outside of the stable range.

In another embodiment, the dominant wireless sensing device may not beoperated continuously, but may be operated at a measurement interval.For example, this may be appropriate where the key parameter is one thattakes a period of time to monitor or determine, such as NIBP. In thatcase, the dominant wireless sensing device may be operated at a frequentand regular interval. Thus, a minimum measurement interval may also beset for the dominant wireless monitor that may be utilized when thestability index is in the stable range. The monitoring regulation module23 may then increase the measurement frequency proportional to thestability index as the stability index veers out of the normal range,such as increasing the measurement interval to continuous monitoringoperation or the most frequent monitoring interval possible given theoperating constraints of the relevant wireless monitoring device. Theminimum measurement interval may be set relatively high to account forthe fact that the relevant wireless sensing device is the dominantdevice.

The stability index is an indictor of the stability of the key parametermeasured by the dominant wireless sensing device. For example, thestability index may be any value that indicates whether the keyparameter is in a normal range for the patient and remains unchanged fora period of time. The stability index may be determined based on whetherthe key parameter dataset contains values within a predetermined range,which could be a patient-specific normal range developed based onrelevant physiological data previously recorded from the patient, orcould be a population-normal range for the demographic relevant to thepatient. To provide just one exemplary embodiment, the stability indexmay be a value on a linear scale between stable and critical, such as ona scale between 1 and 10, where 1 represents that the values in the keyparameter dataset are squarely within a stringent threshold rangerepresenting normal for the patient and has been in that range for atleast a predetermined amount of time, and 10 represents a criticallyunstable, life threatening emergency that requires immediateintervention by a clinician. In other embodiments, the stability indexmay be any series of values capable of being used by the softwarealgorithm of the monitoring regulation module 23 to represent thestability of the key parameter dataset 41 a being measured by thedominant wireless sensing device.

For example, people with chronic heart problems oftentimes experienceirregular respiration, and thus for such patients it may be appropriateto set respiration as the key parameter. In such an embodiment, thestability index may be calculated as the standard deviation of therespiratory frequency distribution. The value of the respiratorystability index can be classified as within normal range or out ofnormal range.

In certain embodiments, the monitoring regulation module 23 may beconfigured such that the key parameter and dominant wireless sensingdevice are rotated amongst at least two of the wireless sensing devicesin the monitoring network 51. For example, two or more of the wirelesssensing devices 3 a-3 e may be designated based on the patient'scondition, diagnosis, treatment history, etc., and the dominantdesignation may be rotated amongst those sensors. For example, amonitoring system 1 for a patient with a diagnosed cardiac issue mayhave the wireless ECG sensing device 3 a and the wireless SpO2 sensingdevice 3 c assigned as the possible dominant wireless sensing devices,and the assignment of the dominant position may be traded between thosetwo wireless sensing devices. Alternatively or additionally, theassignment of the dominant wireless sensing device may be rotatedbetween wireless sensing devices on a periodic basis. The change to anew dominant wireless sensing device may be made based on any number offactors. For example, a new dominant wireless sensing device may beassigned between the possible dominant devices if the current dominantwireless sensing device is indicating low battery power or ismalfunctioning. Alternatively or additionally, a new dominant wirelesssensing device may be selected and assigned based on the parameterdatasets collected by the subordinate wireless sensing devices, such asif a periodic check by one of the subordinate wireless sensing devicesindicate a change in the relevant monitored parameter. In that instance,the parameter dataset indicating the change may be assigned as the newkey parameter dataset, either for a period of time or indefinitely, andthe associated wireless sensing device may be assigned as the newdominant wireless sensing device.

The hub device 15 may communicate with a host network 30 via a wirelesscommunication link 28, such as to transmit the parameter datasets forthe respective wireless sensing devices 3 a-3 e for storage in thepatient's medical record. The hub 15 has receiver/transmitter 25 thatcommunicates with a receiver/transmitter 31 associated with the hostnetwork 30 on communication link 28, which may operate according to anetwork protocol appropriate for longer-range wireless transmissions,such as on the wireless medical telemetry service (WMTS) spectrum or ona Wi-Fi-compliant wireless local area network (LAN). The host network 30may be, for example, a local computer network having servers housedwithin a medical facility treating the patient, or it may be acloud-based system hosted by a cloud computing provider. The hostnetwork 30 may include a medical records database 33 housing the medicalrecords for the patient, which may be updated to store the parameterdatasets recorded and transmitted by the various wireless sensingdevices 3 a-3 e. The host network 30 may further include other patientcare databases, such as for monitoring, assessing, and storingparticular patient monitoring data. For example, the host network mayinclude an ECG database, such as the MUSE ECG management system producedby General Electric Company of Schenectady, N.Y.

In various embodiments, the hub device 15 may contain software forprocessing the physiological signals recorded by the various wirelesssensing devices 3 a-3 e. For example, in one embodiment the individualwireless sensing device 3 a-3 e may perform minimal or no signalprocessing on the physiological data measured from the patient, and maysimply transmit the digitized physiological data recorded from therespective sensors 9 a-9 e. Software stored in the hub device 15 maythen be executed on the processor 19 to calculate various usefulparameters from the physiological data, as is explained above withrespect to the exemplary wireless sensing devices 3 a-3 d depicted inFIG. 1. In still other embodiments, minimal or no signal processing maybe performed in the hub device 15, and the hub device 15 may simplyserve to relay the parameter datasets from the wireless sensing devices3 a-3 e to the host network 30. In such an embodiment, the computingsystem 35, including the monitoring regulation module 23, may reside inthe host network 30, as is depicted in the embodiment of FIG. 2.

In the embodiment of FIG. 2, the hub device 15 is omitted and thewireless sensing devices 3 a-3 e communicate directly with the hostnetwork 30. Thus, the receiver/transmitter 5 a-5 e of each wirelesssensing device 3 a-3 e may communicate with a receiver/transmitter 31associated with the host network 30 by the respective communication link11 a-11 e. The communication link 11 a-11 e in this embodiment mayoperate according to any wireless communication protocol listed above.It may be desirable to operate the communication according to a wirelesscommunication protocol that is appropriate for longer-rangetransmission. For example, the wireless sensing devices 3 a-3 e maycommunicate with the host network 30 on the WMTS spectrum or on theWi-Fi spectrum. In such an embodiment, receiver/transmitters 31 may beprovided throughout a patient care facility, such as a hospital, asneeded based on the system configuration and the location of patientsbeing monitored by wireless sensor devices. The host network 30 mayhouse the computing system 35 containing the monitoring regulationmodule 23, and thus the calculation of the patient condition index andmeasurement interval assignment may be conducted by the computing system35 housed in the host network 30. Further, the host network 30 mayprovide one or more central monitoring stations, such as user interfacesat central locations for attending clinicians to monitor patientconditions and/or receive alarm notifications.

FIG. 3 provides a system diagram of an exemplary embodiment of thecomputing system 35 having a monitoring regulation module 23 executableto control the wireless sensing devices 3 a-3 e. The computing system 35includes a processor 19, memory 21, software 37, and communicationinterface 39. The processor 19 loads and executes software 37 frommemory 21, including the monitoring regulation module 23, which is anapplication within the software 37. Each monitoring regulation module 23includes computer-readable instructions that, when executed by thecomputing system 35 (including the processor 19), direct the operationas described in detail herein, including to calculate the patientcondition index and assign the measurement intervals for the wirelesssensing devices 3 a-3 e.

Although the computing system 35 as depicted in FIG. 3 includes onesoftware element 37 encapsulating one monitoring regulation module 23,it should be understood that one or more software elements having one ormore modules may provide the same operation. Similarly, while thedescription provided herein refers to a single computing system 35having a single processor 19, it is to be recognized thatimplementations of such systems can be performed using one or moreprocessors, which may be communicatively connected, and suchimplementations are considered to be within the scope of thedescription. Likewise, the computing system 35 may be implemented asseveral computing systems networked together, including in a cloudcomputing environment. Such an embodiment may be utilized, for example,where the computing system 35 is part of the host network 30.

The memory 21, which includes the medical record database 33, cancomprise any storage media, or group of storage media, readable byprocessor 19 and/or capable of storing software 37. The memory 21 caninclude volatile and non-volatile, removable and non-removable storagemedia implemented in any method or technology for storage ofinformation, such as computer-readable instructions, data structures,program modules, or other data. Memory 21 can be implemented as a singlestorage device but may also be implemented across multiple storagedevices or sub-systems. For example, the software 37 may be stored on aseparate storage device than the medical record database 33. Further, insome embodiments the memory 21 may also store the medical recorddatabase 33, which could also be distributed, and/or implemented acrossone or more storage media or group of storage medias accessible withinthe host network 30. Similarly, medical record database 33 may encompassmultiple different sub-databases at different storage locations and/orcontaining different information which may be stored in differentformats.

Examples of memory devices, or storage media, include random accessmemory, read only memory, magnetic discs, optical discs, flash memory,virtual memory, and non-virtual memory, magnetic sets, magnetic tape,magnetic disc storage or other magnetic storage devices, or any othermedium which can be used to storage the desired information and that maybe accessed by an instruction execution system, as well as anycombination or variation thereof, or any other type of storage medium.Likewise, the storage media may be housed locally with the processor 19,or may be distributed in one or more servers, which may be at multiplelocations and networked, such as in cloud computing applications andsystems. In some implementations, the store media can be anon-transitory storage media. In some implementations, at least aportion of the storage media may be transitory. Memory 21 may furtherinclude additional elements, such a controller capable, of communicatingwith the processor 19.

The communication interface 39 is configured to provide communicationbetween the processor 19 and the various other aspects of the system 1,including the wireless sensing devices 3 a-3 e to receive the parameterdatasets 41 a-41 e and the battery status 43 a-43 e of each respectivewireless sensing device 3 a-3 e and to transmit the operation command 45a-45 e to each respective wireless sensing device 3 a-3 e. For example,the communication interface 39 may include the receiver/transmitters 17and 25, and/or the receiver/transmitter 31 described above with respectto the various depicted embodiments.

FIG. 4 depicts one embodiment of a method 80 of monitoring a patient. Atstep 82, a dominant wireless sensing device is assigned. At step 83, akey parameter is recorded from the dominant wireless sensing device, anda stability indicator for the key parameter is determined at step 86.The subordinate sensing devices are then operated at step 90 based onthe stability indicator. The operation of the subordinate wirelesssensing devices based on the stability indicator may take any number offorms, examples of which are provided in FIGS. 6-8.

FIGS. 5-8 depict other embodiments of the method 80 of monitoring apatient. A key parameter is selected at step 81 and the wirelessmonitoring device associated with the key parameter is assigned thedominant position at step 82. As explained herein, the dominant wirelesssensing device may be assigned, for example, based on a diagnosis forthe patient or based on a medical history of the patient. For example, aclinician may input one or more key parameters which will provide themost relevant data for the patient, and the dominant wireless sensingdevice may then be assigned based on the indicated key parameter. Inanother embodiment, the key parameter and/or dominant wireless sensingdevice may be assigned automatically by the system, such as byinformation provided or accessed in the patient's medical record storedin the medical records database 33. In the depicted embodiment, the keyparameter dataset is continuously measured at step 83 and is transmittedat step 84. As described above, other embodiments may operate such thatthe key parameter is measured with the dominant sensing device at aregular periodic interval. The transmission may also be continuous, orthe parameter dataset may be transmitted at predefined intervals. Thekey parameter dataset is received at step 85 and the stability indicatorcalculated at step 86. The stability indicator is then used to controlthe subordinate sensing devices, such as by the method steps exemplifiedin FIGS. 6-8. At step 81, a key parameter is selected.

In the embodiment of FIG. 6, the monitoring regulation module 23determines at step 89 whether the stability indicator calculated at step86 is within a predetermined range. As described above, thepredetermined range for the stability indicator is a range thatindicates that the key parameter is stable, which is a proxy for thepatient condition as a whole. If the stability indicator is within thepredetermined stable range, then one or more of the subordinate sensingdevices may be turned off at step 91 such that those subordinatewireless sensing devices no longer measure any physiological parameterfrom the patient or transmit a parameter dataset. Thus, thosesubordinate sensing devices that are turned off are utilizing little tono power, other than that used to provide minimal operation to continuereceiving relevant operation commands from the computing system 35, suchas to wake up the subordinate sensing device if the stability indicatorfalls out of the predetermined range. If at step 89 the stabilityindicator is not within the predetermined range, then the subordinatesensing devices may be operated at step 100, such as to continuouslymonitor the subordinate physiological parameters for a predeterminedamount of time, or to measure the subordinate physiological parametersfor a predetermined amount of time or to take a predetermined amount ofmeasurements.

FIG. 7 depicts another embodiment where the subordinate sensing devicesare operated at a measurement interval set according to the stabilityindicator. If the stability indicator is within the predetermined rangeat step 89, then step 93 may be executed to operate one or more ofsubordinate sensing devices at the minimum measurement interval for therespective sensing device. As explained above, each subordinate sensingdevice may have different minimum measurement interval, which may be setbased on the type of physiological parameter measured, the patientcondition, etc. If at step 89 the stability indicator is not within thepredetermined range, the monitoring regulation module 23 may furtherdetermine whether the stability indicator is within a predeterminedcritical range at step 94. If the stability indicator is within acritical range, then the maximum measurement interval, such ascontinuous monitoring, will be assigned for each of the subordinatesensing devices at step 100 a and an alarm will be generated at step101. If at step 94 the stability indicator is not within the criticalrange, and is thus somewhere between stable and critical, then anappropriate measurement will be assigned for each subordinate sensingdevice at step 96 based on the value of the stability indicator. Forexample, a measurement interval somewhere between the minimum andmaximum interval for each subordinate sensing device may be assigned.Each subordinate sensing device is then operated at step 100 b accordingto the assigned measurement interval.

FIG. 8 depicts another embodiment of a method 80 for monitoring apatient where the subordinate sensing devices are operated in a lowpower mode indicated by step 95, if it is determined at step 89 that thestability indicator is within the predetermined stable range. Thesubordinate sensing devices may be operated in low power mode tocontinuously measure the relevant physiological parameters, or maymeasure the relevant physiological parameters from the patient at apredefined interval. For example, the subordinate wireless sensingdevices may keep measuring the relevant physiological parameter from thepatient and may store a predetermined amount of the most recentmeasurement data, but may not transmit the parameter dataset unlessinstructed to do so by the monitoring regulation module 23. As shown inFIG. 8, the predetermined amount of most recent measurement data storedby the wireless monitoring device may be transmitted if the stabilityindicator is determined to be outside of the predetermined stabilityrange, as is indicated at step 98. Thus, if an incident occurs with thepatient where the key parameter suddenly deteriorates, then monitoringdata is available from one or more of the subordinate devices that mayalso capture the time period of the incident. The subordinate sensingdevices may then be operated at step 100 to continually monitor theother parameters from the patient.

Alternatively or additionally, the devices may modify their operation inany number of other ways in order to consume less power when the patientis determined to be stable and less monitoring is needed. For example,each wireless sensing device may transmit a lesser amount of parameterdata, such as a most relevant subset of the parameter data, or maytransmit at a lesser frequency. In another example, the wireless sensordevices may modify their sensing operation to one that demands lessenergy, such as by operating fewer sensors or operating the sensors in away that uses less energy. For instance, a wireless ECG sensing deviceor a wireless EEG sensing device may reduce the number of leads itmeasures from. In the example of an ECG sensing device, the device mayreduce from a 12-lead operation to a 5-lead operation or a 3-leadoperation.

In various embodiments, the monitoring regulation module 23 may employmultiple different methods for controlling the subordinate wirelesssensing devices 3 a-3 e in the monitoring network 51. For example, twoor more of the exemplary methods depicted in FIGS. 6-8 may be utilizedsimultaneously, as each may be employed to control different wirelesssensing devices in the monitoring network 51.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to make and use the invention. The patentable scope of the inventionis defined by the claims, and may include other examples that occur tothose skilled in the art. Such other examples are intended to be withinthe scope of the claims if they have structural elements that do notdiffer from the literal language of the claims, or if they includeequivalent structural elements with insubstantial differences from theliteral languages of the claims.

We claim:
 1. A patient monitoring system comprising: at least twowireless sensing devices, each wireless sensing device configured tomeasure a different physiological parameter from a patient andwirelessly transmit a parameter dataset; a receiver that receives eachparameter dataset from each of the at least two wireless sensingdevices; a processor; a monitoring regulation module executable on theprocessor to: assign one of the at least two wireless sensing devices asa dominant wireless sensing device and at least one of the remainingwireless sensing devices as a subordinate wireless sensing device,wherein the physiological parameter measured by the dominant wirelesssensing device is a key parameter and the parameter dataset transmittedby the dominant wireless sensing device is a key parameter dataset;determine a stability indicator for the key parameter based on the keyparameter dataset from the dominant wireless sensing device; andselectively operate the subordinate wireless sensing device based on thestability indicator for the key parameter, wherein at least one of thesubordinate wireless sensing devices is turned off when the stabilityindicator is within a predetermined range, such that the subordinatewireless sensing device no longer measures any physiological parameterfrom the patient or transmits any parameter dataset.
 2. The patientmonitoring system of claim 1, wherein the dominant wireless sensingdevice is operated to continuously measure the key parameter.
 3. Thepatient monitoring system of claim 1, wherein the dominant wirelesssensing device is assigned based on one of a diagnosis or a treatmenthistory for the patient.
 4. The patient monitoring system of claim 1,wherein the key parameter and dominant wireless sensing device arerotated amongst at least two of the two or more wireless sensingdevices.
 5. A method of monitoring a patient, the method comprising:providing two or more wireless sensing devices, each wireless sensingdevice configured to measure a different physiological parameter from apatient and communicatively connected to a computing system having aprocessor; assigning at the processor one of the at least two wirelesssensing devices as a dominant wireless sensing device and at least oneof the remaining wireless sensing devices as a subordinate wirelesssensing device; operating the dominant wireless sensing device tomeasure a key parameter from a patient and wirelessly transmit a keyparameter dataset; determining a stability indicator for the keyparameter based on the key parameter dataset; and selectively operatingthe at least one subordinate wireless sensing device based on thestability indicator for the key parameter, wherein selectively operatingthe subordinate wireless sensing device includes turning off at leastone subordinate wireless sensing device when the stability indicator forthe key parameter is within a predetermined range, such that therespective subordinate wireless sensing device does not measure anyphysiological parameter from the patient or transmit any parameterdataset.
 6. The method of claim 5, further comprising operating thedominant wireless sensing device to continuously measure the keyparameter.
 7. The method of claim 5, wherein the dominant wirelesssensing device is assigned based on one of a diagnosis or a medicalhistory for the patient.
 8. The method of claim 5, further comprisingassigning a new dominant wireless sensing device by selecting one of thesubordinate wireless sensing devices to be the dominant wireless sensingdevice.
 9. The method of claim 8, wherein the new dominant wirelesssensing device is assigned based on previously transmitted parameterdatasets or based on battery power constraints.
 10. The method of claim5, wherein selectively operating the subordinate wireless sensing deviceincludes operating at least one of the subordinate wireless sensingdevices upon determining that the stability indicator for the keyparameter is outside of a predetermined range.
 11. A patient monitoringsystem comprising: at least two wireless sensing devices, each wirelesssensing device configured to measure a different physiological parameterfrom a patient and wirelessly transmit a parameter dataset; a receiverthat receives each parameter dataset from each of the at least twowireless sensing devices; a processor; a monitoring regulation moduleexecutable on the processor to: assign one of the at least two wirelesssensing devices as a dominant wireless sensing device and at least oneof the remaining wireless sensing devices as a subordinate wirelesssensing device, wherein the physiological parameter measured by thedominant wireless sensing device is a key parameter and the parameterdataset transmitted by the dominant wireless sensing device is a keyparameter dataset; determine a stability indicator for the key parameterbased on the key parameter dataset from the dominant wireless sensingdevice; and selectively operate the subordinate wireless sensing devicebased on the stability indicator for the key parameter, wherein at leastone of the subordinate wireless sensing devices is operated in a lowpower mode when the stability indicator for the key parameter is withina predetermined range, such that the respective subordinate wirelesssensing device does not transmit any parameter dataset.
 12. The patientmonitoring system of claim 11, wherein the subordinate wireless sensingdevice in the low power mode continuously measures the respectivephysiological parameter from the patient and stores a predeterminedamount of most recent parameter data.
 13. The patient monitoring systemof claim 11, wherein the subordinate wireless sensing device in the lowpower mode measures the respective physiological parameter from thepatient at a predefined interval and stores a predetermined amount ofmost recent parameter data.
 14. The patient monitoring system of claim11, wherein the dominant wireless sensing device is assigned based onone of a diagnosis or a treatment history for the patient.
 15. Thepatient monitoring system of claim 11, wherein the key parameter anddominant wireless sensing device are rotated amongst at least two of thetwo or more wireless sensing devices.
 16. A patient monitoring systemcomprising: at least two wireless sensing devices, each wireless sensingdevice configured to measure a different physiological parameter from apatient and wirelessly transmit a parameter dataset; a receiver thatreceives each parameter dataset from each of the at least two wirelesssensing devices; a processor; a monitoring regulation module executableon the processor to: assign one of the at least two wireless sensingdevices as a dominant wireless sensing device and at least one of theremaining wireless sensing devices as a subordinate wireless sensingdevice, wherein the physiological parameter measured by the dominantwireless sensing device is a key parameter and the parameter datasettransmitted by the dominant wireless sensing device is a key parameterdataset; determine a stability indicator for the key parameter based onthe key parameter dataset from the dominant wireless sensing device; andselectively operate the subordinate wireless sensing device based on thestability indicator for the key parameter, including assigning ameasurement interval for each of the one or more subordinate wirelesssensing devices based on the stability indicator.
 17. The patientmonitoring system of claim 16, wherein the dominant wireless sensingdevice is assigned based on one of a diagnosis or a treatment historyfor the patient.
 18. The patient monitoring system of claim 16, whereinthe key parameter and dominant wireless sensing device are rotatedamongst at least two of the two or more wireless sensing devices.
 19. Amethod of monitoring a patient, the method comprising: providing two ormore wireless sensing devices, each wireless sensing device configuredto measure a different physiological parameter from a patient andcommunicatively connected to a computing system having a processor;assigning at the processor one of the at least two wireless sensingdevices as a dominant wireless sensing device and at least one of theremaining wireless sensing devices as a subordinate wireless sensingdevice; operating the dominant wireless sensing device to measure a keyparameter from a patient and wirelessly transmit a key parameterdataset; determining a stability indicator for the key parameter basedon the key parameter dataset; and selectively operating the at least onesubordinate wireless sensing device based on the stability indicator forthe key parameter, including operating at least one of the subordinatewireless sensing devices in a low power mode when the stabilityindicator for the key parameter is within a predetermined range, suchthat the subordinate wireless sensing device does not transmit anyparameter dataset.
 20. The method of claim 19, wherein the dominantwireless sensing device is assigned based on one of a diagnosis or amedical history for the patient.
 21. The method of claim 19, furthercomprising assigning a new dominant wireless sensing device by selectingone of the subordinate wireless sensing devices to be the dominantwireless sensing device.
 22. The method of claim 21, wherein the newdominant wireless sensing device is assigned based on previouslytransmitted parameter datasets or based on battery power constraints.23. The method of claim 19, wherein the subordinate wireless sensingdevice in the low power mode continuously measures a physiologicalparameter from the patient and stores a predetermined amount of mostrecent measurement data.
 24. The method of claim 19, wherein thesubordinate wireless sensing device in the low power mode measures aphysiological parameter from the patient at a predefined interval andstores a predetermined amount of most recent measurement data.
 25. Amethod of monitoring a patient, the method comprising: providing two ormore wireless sensing devices, each wireless sensing device configuredto measure a different physiological parameter from a patient andcommunicatively connected to a computing system having a processor;assigning at the processor one of the at least two wireless sensingdevices as a dominant wireless sensing device and at least one of theremaining wireless sensing devices as a subordinate wireless sensingdevice; operating the dominant wireless sensing device to measure a keyparameter from a patient and wirelessly transmit a key parameterdataset; determining a stability indicator for the key parameter basedon the key parameter dataset; and selectively operating the at least onesubordinate wireless sensing device based on the stability indicator forthe key parameter, including assigning a measurement interval for eachof the one or more subordinate wireless sensing devices based on thestability indicator.
 26. The method of claim 25, wherein the dominantwireless sensing device is assigned based on one of a diagnosis or amedical history for the patient.
 27. The method of claim 25, furthercomprising assigning a new dominant wireless sensing device by selectingone of the subordinate wireless sensing devices to be the dominantwireless sensing device.
 28. The method of claim 27, wherein the newdominant wireless sensing device is assigned based on previouslytransmitted parameter datasets or based on battery power constraints.